Cloud Computing and SOA Convergence in Your Enterprise: A Step ...

SOA Meets Cloud Computing 7
services among enterprise applications invites reusability and significantly
reduces the need for redundant application services.
What is unique about SOA is that it is as much a strategy as a set of technologies,
and it is really more of a journey than a destination.
SOA Meets Cloud Computing
So, what does SOA have to do with cloud computing, and why did we write a
book about it Cloud computing is any IT resource, including storage, database,
application development, application services, and so on, that exists
outside of the firewall that may be leveraged by enterprise IT over the Internet.
The core idea behind cloud computing is that it is much cheaper to leverage
these resources as services, paying as you go and as you need them,
than it is to buy more hardware and software for the data center. There are
other advantages as well.
Cloud computing allows you to expand and contract your costs in direct
proportion to your needs. Moreover, it shifts some of the risk around expanding
your IT resources from the enterprise to the cloud computing provider.
We cover the business benefits of cloud computing in Chapter 4,
“Making the Business Case for Clouds.” Also, cloud computing abstracts those
using the cloud computing–delivered IT resource from the management of
those resources.
The relationship between cloud computing and SOA is that cloud computing
provides IT resources you can leverage on demand, including resources
that host data, services, and processes. Thus, you have the ability to
extend your SOA outside of the enterprise firewall to cloud computing providers,
seeking the benefits already described. We describe this process as
“SOA using cloud computing,” and it is the objective of this book to show
you how it is done.
SOA is important to cloud computing for a few key reasons:
It is a good approach to architecture that deals with the proper formation
of the information systems using mechanisms that make them work
and play well together, inside and outside of the enterprise.
In order to take advantage of cloud computing, you need interfaces and
architectures that can reach out and touch cloud computing resources.
While many believe they can simply create quick and dirty links between
core enterprise information systems and cloud computing resources, the